Island Lake 2017
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Island Lake 2017 ALBERTA LAKE MANAGEMENT SOCIETY’S LAKEWATCH PROGRAM LakeWatch has several important objectives, one of which is to collect and interpret water quality data on Alberta Lakes. Equally important is educating lake users about their aquatic environment, encouraging public involvement in lake management, and facilitating cooperation and partnerships between government, industry, the scientific community and lake users. LakeWatch Reports are designed to summarize basic lake data in understandable terms for a lay audience and are not meant to be a complete synopsis of information about specific lakes. Additional information is available for many lakes that have been included in LakeWatch and readers requiring more information are encouraged to seek those sources. ALMS would like to thank all who express interest in Alberta’s aquatic environments and particularly those who have participated in the LakeWatch program. These people prove that ecological apathy can be overcome and give us hope that our water resources will not be the limiting factor in the health of our environment. ALMS is happy to discuss the results of this report with our stakeholders. If you would like information or a public presentation, contact us at [email protected]. ACKNOWLEDGEMENTS The LakeWatch program is made possible through the dedication of its volunteers. We would like to extend a special thanks to Jim Montague for the time and energy put into sampling Island Lake in 2017. We would also like to thank Elashia Young and Melissa Risto who were summer technicians in 2017. Executive Director Bradley Peter and LakeWatch Coordinator Laura Redmond was instrumental in planning and organizing the field program. This report was prepared by Laura Redmond and Bradley Peter. The Beaver River Watershed, the Lakeland Industry and Community Association, Environment Canada, and Alberta Environment and Parks are major sponsors of the LakeWatch program. ISLAND LAKE Island Lake is topographically interesting, in that it has many islands and bays. The lake is located in the County of Athabasca, about 20 km northwest of the town of Athabasca. The west side is accessible from Highway 2, which passes north through Athabasca from Edmonton then along the west shore of the lake enroute to the Town of Slave Lake. Public Access at Island Lake is available at several locations on the west side within the summer villages. Boats may be launched at most sites. Island Lake—photo by Randi Newton 2012 Homesteads in the region were first established in about 1908. Seasonal cottage development on Island Lake began with subdivision of land on the west side in 1956; the summer village of Island Lake was incorporated the following year. In 1983, a second summer village, Island Lake South, was incorporated. Almost all residential development around the lake is located on the west shore within the two summer villages. Island Lake is a medium-sized water body with a surface area of 7.81 km2 and a drainage basin of 63.2 km2. The main basin is shallow: the maximum depth is about 12 m, but most of the basin is less than 6 m deep. The deepest part of the lake is in the north bas which reaches a depth of 18 m. The main basin of Island Lake is fairly shallow. A smaller, deeper northern basin is connected to the main basin by a narrow channel. Shallow areas in the main basin support dense beds of aquatic vegetation. Groundwater inflow was measured by University of Alberta researchers in 1986. Groundwater was estimated to contribute 4% of total water inflow. Island Lake’s drainage basin is about 8 times the size of the lake. The main inflow drains from Ghost Lake and the northwestern portion of the drainage basin. Several intermittent streams carry runoff to the lake from other portions of the drainage basin. The outflow, Island Creek, flows from the east side of the lake southeast for about 5 km to the Athabasca River. Island Creek is choked with aquatic plants and has limited flow. About 27% of the drainage basin has been cleared, including areas of land around the south and west sides of Island Lake; most of the northern and northwestern regions remain forested. The soils around Island Lake have severe to very severe limitations on agriculture. The most abundant trees are trembling aspen, balsam poplar, white spruce, balsam fir, and white birch. Black spruce grown on poorly drained areas. Mature stands are rare becau of past fires and clearing. Mature mixed stands can be found on the large islands and in patches along the north shore of Island Lake. There are extensive areas of Crown Land near the lake, including most of the islands. Several of these areas have been reserved fo recreation. Island Lake is a popular destination for the fishing of perch, walleye, pike, and burbot. In fact, the Alberta size record for yellow perch came from Island Lake in 1982, measuring 2 lbs. 15.5 oz. Mitchell, P and E. Prepas. (1990). Atlas of Alberta Lakes, University of Alberta Press. Available at: http://sunsite.ualberta.ca/Projects/Alberta-Lakes/ METHODS Profiles: Profile data is measured at the deepest spot in the main basin of the lake. At the profile site, temperature, dissolved oxygen, pH, conductivity and redox potential are measured at 0.5- 1.0 m intervals. Additionally, Secchi depth is measured at the profile site and used to calculate the euphotic zone. On one visit per season, metals are collected at the profile site by hand grab from the surface and at some lakes, 1 m off bottom using a Kemmerer. Composite samples: At 10-sites across the lake, water is collected from the euphotic zone and combined across sites into one composite sample. This water is collected for analysis of water chemistry, chlorophyll-a, nutrients and microcystin. Quality control (QC) data for total phosphorus was taken as a duplicate true split on one sampling date. ALMS uses the following accredited labs for analysis: Routine water chemistry and nutrients are analyzed by Maxxam Analytics, chlorophyll-a and metals are analyzed by Alberta Innovates Technology Futures (AITF), and microcystin is analyzed by the Alberta Centre for Toxicology (ACTF). In lakes where mercury samples are taken, they are analyzed by the Biogeochemical Analytical Service Laboratory (BASL). Invasive Species: Monitoring for invasive quagga and zebra mussels involved two components: monitoring for juvenile mussel veligers using a 63 μm plankton net at three sample sites and monitoring for attached adult mussels using substrates installed at each lake. Data Storage and Analysis: Data is stored in the Water Data System (WDS), a module of the Environmental Management System (EMS) run by Alberta Environment and Parks (AEP). Data goes through a complete validation process by ALMS and AEP. Users should use caution when comparing historical data, as sampling and laboratory techniques have changed over time (e.g. detection limits). For more information on data storage, see AEP Surface Water Quality Data Reports at aep.alberta.ca/water. Data analysis is done using the program R.1 Data is reconfigured using packages tidyr 2 and dplyr 3 and figures are produced using the package ggplot2 4. Trophic status for each lake is classified based on lake water characteristics using values from Nurnberg (1996)5. The Canadian Council for Ministers of the Environment (CCME) guidelines for the Protection of Aquatic Life are used to compare heavy metals and dissolved oxygen measurements. Pearson’s Correlation tests are used to examine relationships between TP, chlorophyll-a, TKN and Secchi depth, providing a correlation coefficient (r) to show the strength (0-1) and a p-value to assess significance of the relationship. 1 R Core Team (2016). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL https://www.R-project.org/. 2 Wickman, H. and Henry, L. (2017). tidyr: Easily Tidy Data with ‘spread ( )’ and ‘gather ( )’ Functions. R package version 0.7.2. https://CRAN.R-project.org/package=tidyr. 3 Wickman, H., Francois, R., Henry, L. and Muller, K. (2017). dplyr: A Grammar of Data Manipulation. R package version 0.7.4. http://CRAN.R-project.org/package=dplyr. 4 Wickham, H. (2009). ggplot2: Elegant Graphics for Data Analysis. Springer-Verlag New York. 5Nurnberg, G.K. (1996). Trophic state of clear and colored, soft- and hardwater lakes with special consideration of nutrients, anoxia, phytoplankton and fish. Lake and Reservoir Management 12: 432-447. BEFORE READING THIS REPORT, CHECK OUT A BRIEF INTRODUCTION TO LIMNOLOGY AT ALMS.CA/REPORTS WATER CHEMISTRY ALMS measures a suite of water chemistry parameters. Phosphorus, nitrogen, and chlorophyll-a are important because they are indicators of eutrophication, or excess nutrients, which can lead to harmful algal/cyanobacteria blooms. One direct measure of harmful cyanobacteria blooms are Microcystins, a common group of toxins produced by cyanobacteria. See Table 2 for a complete list of parameters. The average total phosphorus (TP) concentration for Island Lake was 18 μg/L (Table 2), falling into the mesotrophic, or moderately productive trophic classification. Historically, this TP average is lower than past years. TP increased over the course of the sampling season, peaking in September (Figure 1). Average chlorophyll-a concentrations in 2017 was 7 μg/L (Table 2), also putting Island Lake into the mesotrophic classification. Chlorophyll-a concentrations also increased over the course of the sampling season, peaking at 12.1 μg/L on August 20. Finally, average TKN concentration was 1.175 mg/L (Table 2), and concentrations fluctuated very little throughout the summer (Figure 1). Average pH was measured as 8.42 in 2017, buffered by moderate alkalinity (220 mg/L CaCO3) and bicarbonate (257.5 mg/L HCO3). Calcium and sodium were the dominant ions contributing to a low conductivity of 437.5 μS/cm (Table 2).